• Abstract class useful for achieving the partial abstraction, Interface use for Fully Abstraction.
  • In the Abstract class All data members are not always static and final, In the interface, all data members always are static and final.
  • In abstract Class Method never always public and abstract, In Interface method are always abstract and public.
  • The abstract is always Heavy Weight class, Interface is always light weight.
  • Abstract Class contain abstract method and Concrete method also, Interface contain only Concrete method always
  • By abstract class can’t achieve multiple inheritances, By Interface can achieve Multiple Inheritance.
  • Abstract class always faster rather than the interface.
  • An abstract class provides some common functionality(non-abstract method) and some functionality which will very for every subclass, interface provide only those functions which are very for every subclass.